On Wed, May 06, 2015 at 06:58:55AM -0500, Aravind Gopalakrishnan wrote: > diff --git a/arch/x86/kernel/cpu/mcheck/mce.c > b/arch/x86/kernel/cpu/mcheck/mce.c > index e535533..6d218ac 100644 > --- a/arch/x86/kernel/cpu/mcheck/mce.c > +++ b/arch/x86/kernel/cpu/mcheck/mce.c > @@ -1639,7 +1639,8 @@ static void __mcheck_cpu_init_vendor(struct cpuinfo_x86 > *c) > break; > case X86_VENDOR_AMD: > mce_amd_feature_init(c); > - mce_flags.overflow_recov = cpuid_ebx(0x80000007) & 0x1; > + mce_flags.overflow_recov = !!(cpuid_ebx(0x80000007) & BIT(0)); > + mce_flags.succor = !!(cpuid_ebx(0x80000007) & BIT(1));
Yuck, I thought gcc would be smart enough to recognize that we're calling CPUID twice with the same params and save us the work but nooo. asm looks yucky. Oh well, I had to save us the second CPUID read and beef up the commit message: --- From: Aravind Gopalakrishnan <[email protected]> Date: Wed, 6 May 2015 06:58:55 -0500 Subject: [PATCH] x86/mce: Add support for deferred errors on AMD Deferred errors indicate error conditions that were not corrected, but those errors have not been consumed yet. They require no action from S/W (or action is optional). These errors provide info about a latent uncorrectable MCE that can occur when a poisoned data is consumed by the processor. Newer AMD processors can generate deferred errors and can be configured to generate APIC interrupts on such events. SUCCOR stands for S/W UnCorrectable error COntainment and Recovery. It indicates support for data poisoning in HW and deferred error interrupts. Add new bitfield to mce_vendor_flags for this. We use this to verify presence of deferred error interrupts before we enable them in mce_amd.c While at it, clarify comments in mce_vendor_flags to provide an indication of usages of the bitfields. Signed-off-by: Aravind Gopalakrishnan <[email protected]> Cc: Tony Luck <[email protected]> Cc: x86-ml <[email protected]> Cc: linux-edac <[email protected]> Link: http://lkml.kernel.org/r/[email protected] [ beef up commit message, do CPUID(8000_0007) only once. ] Signed-off-by: Borislav Petkov <[email protected]> --- arch/x86/include/asm/mce.h | 15 +++++++++++++-- arch/x86/kernel/cpu/mcheck/mce.c | 10 ++++++++-- 2 files changed, 21 insertions(+), 4 deletions(-) diff --git a/arch/x86/include/asm/mce.h b/arch/x86/include/asm/mce.h index 1f5a86d518db..407ced642ac1 100644 --- a/arch/x86/include/asm/mce.h +++ b/arch/x86/include/asm/mce.h @@ -117,8 +117,19 @@ struct mca_config { }; struct mce_vendor_flags { - __u64 overflow_recov : 1, /* cpuid_ebx(80000007) */ - __reserved_0 : 63; + /* + * overflow recovery cpuid bit indicates that overflow + * conditions are not fatal + */ + __u64 overflow_recov : 1, + + /* + * SUCCOR stands for S/W UnCorrectable error COntainment + * and Recovery. It indicates support for data poisoning + * in HW and deferred error interrupts. + */ + succor : 1, + __reserved_0 : 62; }; extern struct mce_vendor_flags mce_flags; diff --git a/arch/x86/kernel/cpu/mcheck/mce.c b/arch/x86/kernel/cpu/mcheck/mce.c index e535533d5ab8..521e5016aca6 100644 --- a/arch/x86/kernel/cpu/mcheck/mce.c +++ b/arch/x86/kernel/cpu/mcheck/mce.c @@ -1637,10 +1637,16 @@ static void __mcheck_cpu_init_vendor(struct cpuinfo_x86 *c) mce_intel_feature_init(c); mce_adjust_timer = cmci_intel_adjust_timer; break; - case X86_VENDOR_AMD: + + case X86_VENDOR_AMD: { + u32 ebx = cpuid_ebx(0x80000007); + mce_amd_feature_init(c); - mce_flags.overflow_recov = cpuid_ebx(0x80000007) & 0x1; + mce_flags.overflow_recov = !!(ebx & BIT(0)); + mce_flags.succor = !!(ebx & BIT(1)); break; + } + default: break; } -- 2.3.5 -- Regards/Gruss, Boris. ECO tip #101: Trim your mails when you reply. -- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
